Backgroud Functional imaging studies indicate abnormal activities in cortico-limbic network in depression during either task or resting state. The present work was to explore the abnormal spontaneous activity shown with regional homogeneity （ReHo） in depression by resting-state functional magnetic resonance imaging （fMRI）.Methods Using fMRI, the differences of regional brain activity were measured in resting state in depressed vs. healthy participants. Sixteen participants firstly diagnosed with major depressive disorder and 16 controls were scanned during resting state. A novel method based on ReHo was used to detect spontaneous hemodynamic responses across the whole brain.Results ReHo in the left thalamus, left temporal lobe, left cerebellar posterior lobe, and the bilateral occipital lobe was found to be significantly decreased in depression compared to healthy controls in resting state of depression.Conclusions Abnormal spontaneous activity exists in the left thalamus, left temporal lobe, left cerebellar posterior lobe,and the bilateral occipital lobe. And the ReHo may be a potential reference in understanding the distinct brain activity in resting state of depression.
目的探讨慢性应激状态下,以及持续给予盐酸氟西汀后,大鼠海马及前额叶部位环磷酸腺苷反应元件结合蛋白(cAMP-response element binding protein,CREB)水平和磷酸化CREB(p-CREB)表达的变化。方法成年雄性Sprague-Dawley(SD)大鼠50只随机分为三组:应激组26只,药物组12只,对照组12只。应激组与药物组大鼠均经过8周慢性应激刺激,药物组在第1周开始给予盐酸氟西汀(10mg/g,I.P.),直到8周末。8周后行糖水偏好实验和旷场实验,根据8周末糖水偏爱率将应激组大鼠分为应激敏感组和应激适应组。应激结束后将四组大鼠断头处死,采用蛋白免疫印记技术检测大鼠海马、额叶部位CREB和p-CREB水平。结果 8周末应激敏感组糖水偏爱率低于应激适应组、药物组及对照组(均P<0.05);应激敏感组的跨格次数、中心格时间和直立次数低于药物组和对照组(均P<0.05),与应激适应组无统计学差异(均P>0.05)。应激敏感组海马及前额叶中p-CREB水平明显低于应激适应组、药物组及对照组(均P<0.05);四组大鼠海马部位、前额叶CREB表达水平无明显差异。结论海马和额叶部位CREB磷酸化水平可能与应激导致的情绪障碍发生机制相关。
